Attachment clamp



FIG. 1 is a perspective view of an attachment clamp showing my new design;

FIG. 2 is a front elevational view thereof, the rear being identical and the bolt and nuts being shown in broken lines for illustration purposes only;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a side elevational view thereof, both sides being identical; and,

FIG. 5 is a top plan view thereof. 

The ornamental design for an attachment clamp, as shown and described. 